Chrysler Repair: 92 LeBaron 4 Spd Automatic wont shift, chrysler dealer, diagnostic connector

Question
TRANS FLUID AND FILTER CHANGED,NOW TRANS WAN'T SHIFT OUT OF LOW. DID NOTHING ELSE WORKED FINE UNTIL CHANGED

Answer
Hi Fred,
I am not certain why this would happen, except for the possibility that an inappropriate transmission fluid was used in the change. These transmission are very sensitive to the type of fluid used, particularly being harmed by those called Dexron. For that reason I would inquire of the shop that did the change as to which fluid they used. When the trans was manufactured it was recommended to use "ATF Plus" or Mopar Type 7176. As the years have gone by the same trans type has changed fluids to recommend ATF +3, and most recently ATF +4, but still if sold at a Chrysler dealer numbered Type 7176. So see what fluid was used.
If you find that a non-recommended fluid was used, I would get recompensed for the job and go somewhere else promptly that has a fluid power exchanger which doesn't merely drain the fluid from the pans but actually pumps out all the old fluid so you get rid of it. This involves exchanging the full load of fluid which amounts to 10.5 quarts. Then you have a choice to either use ATF +4 or another fluid which I believe is also recommended for this transmission which is Mobil Synthetic Trans Fluid and which is a bit more expensive ($4/qt.). I have heard good reports on the improvement of the shifting of the trans using this synthetic fluid.
If you find that a proper fluid was used, then I would suggest that you get a readout of transmission controller's memory to see what fault code has been noted and stored as a two digit number. The refusal to shift out of second gear is called "limp in mode" and it means that a fault that threatens to harm the trans has been seen. The controller puts it into this mode state and also logs the code into its memory. That readout is accessible thru a special 6-pin plug behind a door at the lower left-hand end of the dash called the bus diagnostic connector. This is not the same as the connector under the hood that accesses only the engine controller memory. The reader that is used has to have that plug and be capable of reading out the code from a Chrysler transmission; one such reader is the Chrysler Diagnostic Readout Box II, or DRB II and would be found at a Chrysler dealer. When you get the readout ask: what is the code number(s), what do they mean, what do they recommend doing, and at what cost. Then write me back with the results for advice before buying into any major repair.
I do hope that the fluid exchange will solve your problem. The repair of these transmissions is expensive and hard to get done properly.
Roland